Noble Tousha Jr. thought his 5-year-old son would like the "Transformers" movie and see in its high-tech, shape-shifting characters a little of himself.

So Noble and his boy, also named Noble (Noble Tousha III, to be exact), went to the IMAX theater in Chantilly late this summer. After the film, dad caught a glimpse of another theater patron's ankle, a flash of silver that was enough to embolden him to walk up and introduce himself. Could his son, he wondered, see the man's prosthetic leg?

Which is how a 5-year-old came to be pulling up his right pants leg while an Afghanistan veteran was pulling up his, the two comparing their artificial limbs.

The veteran's leg had been taken off below the knee by a rocket-propelled grenade. And Noble's?

It happened on an evening in June. Noble's mom, high school PE teacher Holly Tousha (the last name is pronounced "touché"), was weeding the garden at their house in Nokesville while her 2-year-old daughter, Janelle, played nearby. Dad was on his riding lawn mower. Noble was doing what he always seemed to be doing: running around, chasing dad.

Holly called out that he was too close to the mower. And at that instant, he slipped.

"I can't stand the smell of fresh-cut grass anymore," said his dad, who works at a truck accessories company.

It was awful; of course, it was awful. Noble's father was frantic, thinking he had driven right over his son. But Noble was lucky, if you can use that word. The spinning blade had nipped him in the right leg, cutting off most of the heel, shredding the Achilles' tendon and ripping away much of the calf muscle. Holly scooped Noble up and wrapped her shirt around the leg. She sang to him, prayed and said what every mother says, hoping it will be true: Everything will be all right.

Noble and Holly traveled by helicopter to a Virginia hospital. The blade had come within three millimeters of nicking an artery, and there was the very real fear that Noble might not live. Doctors were able to stabilize him. A week later, he was moved to Children's National Medical Center in the District.

"We wanted a place that specialized in children," Holly said.

The hope was to save Noble's leg. But the longer that surgeons John F. Lovejoy III and Michael Boyajian examined Noble, the more doubtful they became.

The questions that faced the Toushas came down to these: Was it better to try to save the leg, understanding that it might require years of operations, with the outcome being a scarred limb and reduced mobility? Or was it better to amputate, end the cycle of painful tissue cleanings and the associated risk of infection, and teach Noble how to walk on an artificial leg?